April's Highlights
The days are now drawing out and the skies are getting dark noticeably later, but there is still plenty to see in the night skies this month...
Last month I mentioned that Comet Garradd was still visible in our skies. Well, it still is and should be for most of the rest of the month too. However it will be getting fainter and so more difficult to see. Moonlight too, will also drown it out. A moderate sized telescope of 6 to 8 inches in aperture should show it well though.
We enjoyed watching the conjunction of Venus and Jupiter last month. If you would like a little more information about how and why these alignments occur, then please take a look at my blog here... Venus will show a beautiful crescent this month easily visible in binoculars and small telescopes and makes a close pass of the Pleiades star cluster, but more of this later...
We have the Lyrid meteor shower gracing our skies this month too. This is a reliable if not well understood shower of fast moving events and this month with the Moon out of the way and its radiant high up in the sky near to the bright star Vega, we should have a good show of these fast moving meteors. The shower peaks on the night of the 21st April through to the 22nd. The best time to observe them will be in the early hours of the 22nd. Wrap up warm!
I mentioned it last month and I think it's worth repeating, the Sun is still very active and will probably become more so as it heads towards solar maximum in 2013. If you are interested in observing our nearest star, please take extreme care and never attempt to look at it directly with any optical aid, including through a camera lens!
Because the Sun is so active, it frequently sends out large jets of matter towards us in the form of highly energetic particles that slam into our Earth's magnetic field which give rise to the Aurora. Most of the time, you can only see the Northern (or Southern) Lights from high latitudes such as Scotland, Iceland, Scandinavia and Canada and Alaska. However, sometimes we receive an extra large flare from the Sun which causes the Auroral 'Oval' around the Earth's poles to expand to lower latitudes. If you are interested in monitoring this activity you can keep up to date on the website SpaceWeather.com
We still have 4 planets on show this month although Jupiter is now getting harder to observer, but more on this below...
The Moon This Month
We start April with a waxing gibbous Moon. This is when just over half the disc that we can see, is illuminated. This is a good time to explore the lunar surface with binoculars or a small telescope along the line dividing night and day. This month provides us with something a little extra too! The Moon wobbles very slightly on its axis and allows us to see 'around the corners' occasionally, so to speak. If you own a telescope of at least 4-inches aperture, on the night between 1st and 5th April, take look at the north-eastern edge of the Moon and see if you can spot the crater Humboldt normally hidden from our view. A Moon map will help you find it. If you would like a recommendation then the Philips Moon Map is good and you can get it at Amazon UK
Full Moon occurs on the 6th. Although the Moon looks bright and attractive it is not the best time to view it through any optical aid as the features are washed out by the light. Shadows help make the features stand out. The Moon will be to the west of and close to the bright star Spica in Virgo. The planet Saturn will be the other 'bright star' a little further to the east.
The 13th April brings us a last quarter Moon. This shows as the illuminated eastern half of the Moon. You can only see a last quarter Moon in the early hours of the morning. The phase is now waning towards New Moon...
And New Moon occurs on 21st April. Even though the Moon and the Sun are in the same region of the sky, you do not always get to see a Total Solar Eclipse, because the Moon is usually slightly above (or sometimes below) the disc of the Sun. Over the next few days you should be able to make out a very thin crescent Moon low down in the west after the Sun has set and so the cycle begins all over again.
If you would like to know more about the Moon, then there is loads of information on my website here.
The Planets this Month
We have lost Mercury in the evening skies now, but there are plenty of other interesting planetary sights to see in April...
You simply cannot miss Venus in the evening skies right throughout the month. As it moves further away from the Sun from our view point, it heads towards the beautiful open cluster of the Pleiades in Taurus the Bull. On the 3rd of the month the planet will be among the group of stars and will be best seen through binoculars. Venus itself is now starting to show us a crescent phase, always a lovely sight in binoculars or especially a small telescope.
Jupiter is now disappearing into the twilight as it heads for its rendezvous with the Sun in mid-May. By this, I mean that the Sun will appear to be between us and the planet, not that Jupiter is going to hit the Sun you understand!
Mars is now past opposition and is quickly moving away from us here on Earth and so is shrinking in apparent size. It will be fading as well, so make the most of it early in the month if you are lucky enough to have access to a telescope to view it. Mars also completes its 'retrograde loop' on the 15th. This is where the planet has seemingly been moving slowly westward against the background stars and will then start to move in its more usual easterly path. If you'd like to know more about the planets retrograde motions, I'll put some more information in a blog post quite soon...
The cream of the crop of planets though in April has to be Saturn...
Saturn reaches opposition on the 15th. This is where it appears to be on the opposite side of the sky from the Sun from our viewpoint here on Earth. During such oppositions, Saturn's famous rings can look brighter than usual for a day or two either side of this time. The rings are quite nicely open as well now so this is the time to really enjoy the planet at its best. You can find it in the constellation Virgo a little to the north-east of the bright star Spica. A telescope of 3 or 4-inches aperture and a moderate magnification of say 100x will show the planet well. See if you can spot some of Saturn's moons too. Titan is the largest and brightest of these.
Naked Eye Astronomy
People often ask me, if there is much you can see without the aid of binoculars or a telescope. I always answer 'yes'!
Ideally you need to get away from town and city lights and out into the dark of the countryside. This will allow you to see many more stars. It is great to start to learn to recognise some of the constellations. Start with the easier ones such as Orion or Leo and do your best to see if you can make out some asterisms as well. Asterisms are patterns of stars that can cover more than one constellation, such as the Summer Triangle of Deneb in Cygnus the Swan, Altair in Aquila the Eagle and Vega in Lyra the Lyre. These can in turn help you to find other constellations and asterisms.
There are some naked eye 'double stars' as well that you can spot. The easiest of these are the stars Mizar and Alcor in the handle of the 'Plough'. You can also just enjoy the changes of the seasons as some constellations set earlier and earlier and other rise to take their place. Also you can wonder at the beauty of the Milky Way especially during the summer months as it arcs in a band of misty light overhead.
Take note of the positions of the planets as well and watch their steady progress across the sky night after night, week after week. Don't forget that there are regular meteor showers to enjoy such as the April Lyrids or the August Perseids and then there is the very occasional naked eye comet...
Deep Sky Highlights of March
This month I'd like to draw your attention to a slightly more sparse area of the sky. Sparse only a t first glance though...
If you found the 'Realm of the Galaxies' I mentioned last month, this will help you to find some interesting stars and objects a little further to the east and north. I'm sure the first thing you'll notice here is the bright star Arcturus, in fact it's hard to miss. Its bright orange colour means that it can be mistaken for the planet Mars, but of course it can't be Mars because that planet is currently in Leo! Arcturus is known as the 'Follower of the Bear', probably due to its track across the heavens in the wake of Ursa Major the Great Bear. Arcturus is the fourth brightest star in the sky and is a red-giant star. It is a very big star, being over 25 times the diameter of the Sun. It is the brightest star in the constellation of Bootes the Herdsman which is shaped a little like a child's kite.
If you draw an imaginary line from Arcturus towards the constellation of Ursa Major, about a third of the way along this line you will come across a lovely 'globular' star cluster, known as M3 which is easily visible in binoculars as an intense misty patch of light. Keep going along this line and you'll come to the star know as Cor Caroli or 'Charles' Heart a reference to King Charles I. This is the brightest star in the constellation of Canes Venatici The Hunting Dog. Cor Caroli is in fact a double star and easily split in a small telescope.
Head from Cor Caroli towards the star Alkaid, the last star in the 'handle' of the Plough and you'll come across another lovely galaxy, this is M63 the Sunflower Galaxy. Again a small telescope should show it as a misty patch. A larger one should start to show some structure... Photographs show this galaxy to be quite 'sunflower' like in appearance.
Keeping heading towards Alkaid in the Plough and a little to the north of this line you might be able to spot the famous 'double' galaxy known as M51 or the 'Whirlpool'. This object is quite difficult to find due to its low surface brightness, but it if you have a telescope of moderate aperture say 8-inches or larger, it is well worth trying to track it down.
If you only have your naked eyes then see how good your eyesight is by having a look at the double star Mizar and Alcor, the next star along from Alkaid in the Plough. If you have good eyesight you should be able to easily discern the two stars. If you have a telescope you should also be able to resolve each of these stars also as doubles. This is a multiple star system.
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